Mayors await word from Corps, DEP

Should a dry detention dam be constructed in South Mountain Reservation?

That answer depends heavily on the outcome of a meeting between the U.S. Army Corps of Engineers and Green Acres, according to Leo Coakley, Millburn Township's consulting engineer for stormwater management issues.

Coakley spoke during a Mayors Council Rahway River Watershed Flood Control meeting last night about status updates concerning the Rahway Watershed Flood Control project, a project designed to better manage floodwater in Millburn and most of Union County during storms.

"The fate of the South Mountain project could rely on this meeting," he said noting that mitigation in South Mountain could cost more than building a detention basin.

The meeting between the U.S. Army Corps of Engineers and Green Acres, which is not open to the public or to the Mayors Council, is scheduled to take place in late March or early April. The two groups will discuss different aspects of stormwater management and flooding.

The Corps presented potential ideas for managing floodwater in Millburn and several Union County municipalities along the East and West Branches of the Rahway River during a meeting in Millburn Town Hall last May. Ideas for South Mountain Reservation included creating a dry detention reservoir between Campbell's and Diamond Mill Ponds that would not store any water or create a lake during normal weather, but would collect water into a "reservoir" during a major storm. Constructing a detention dam in the reservation along with 14,000 ft. of channel improvements, two bridge replacements, and possibly removing two dams along the river are options the Corps has suggested.

According to Coakley, City of Orange officials say property it controls in the reservation is not designated as Green Acres land. Green Acres officials want an inventory of reservation property owned by the city to determine if it is subject to Green Acres funding.

The Mayors Council is hoping the state will give the U.S. Army Corps of Engineers $1.5 million in funding to complete the cost benefit ratio for the whole project. Right now the immediate focus of the project is on building a regional dry detention basin in South Mountain Reservation, according to Millburn mayor Sandra Haimoff. The council hopes to get $370,000 from the state and/or the New Jersey Department of Environmental Protection to complete an environmental assessment of the reservation.

The Union County Board of Freeholders is writing to the state urging it to include funding in the FY 2014 state budget to investigate the potential impacts of developing a regional dry detention basin in South Mountain Reservation, according to an email former Cranford mayor Dan Aschenbach sent to Millburn mayor Sandra Haimoff, other mayors in the Mayors Council, and the Army Corps of Engineers on March 19. Understanding the impacts will help Essex County officials and City of Orange officials understand the potential impacts of the project.

Such impacts include evaluating the basin on water wells and on park inundation of holding back storm water for a few days to let the peak storm pass. The Mayors Council is hoping the New Jersey DEP will earmark some of the money in its budget for the project, Haimoff told The Item of Millburn and Short Hills March 19.

The Mayors Council estimates Tropical Storm Irene caused more than $100 million in damages from Millburn to Rahway, according to Aschenbach. The $100 million figure is what was reported by towns from municipal records, FEMA data, private insurance data and business loss information, Aschenbach explained.